Meanwhile, BP has recalled all 125 vessels working out of Breton Sound with the oil spill response because of the reported illness.

Parish spokesman Kurt Fromherz said the fishermen became sick after coming in contact with dispersant being used to break up the oil.

Officials said the fishermen complained of headaches, shortness breath and dizziness.

Four of those who reported feeling sick were taken to West Jefferson Medical Center at about 7:45 p.m. One was transported by helicopter, another by boat and the other two by ambulance, according to BP.

The other fishermen refused treatment at the dock, BP said.

Medical personnel were being sent to evaluate all the other fishermen working out of Breton Sound as a precaution, BP said.

"No other personnel are reporting symptoms, but we are taking this action as an extreme safeguard," said Coast Guard Chief Petty Officer Robinson Cox, the assistant safety officer at Incident Command Post Houma.

The Coast Guard, the Occupational Safety and Health Administration, the Environmental Protection Agency, and safety officers from BP are investigating the incident.